This invention relates to an improved process for the preparation of 7-amino and 7-substituted amino-desacetoxycephalosporins, of use in human and veterinary medicine.
Great importance has been attained by processes comprising the conversion of the five carbon atom heterocycle in a penicillin to a six atom heterocycle through the ring opening and ring formation sequence, which is promoted by heating a penicillin-sulphoxide solution.